C2 - Atoms, elements and Compounds (Part 1 - Atomic structure)

This is the smallest unit of an element.

• atom

• molecule

• compound

• nucleus

This is any combination of two or more atoms from different elements that are chemically combined.

• compound

• mixture

• element

• pure substance

These subatomic particles are what determine the properties of every atom and make one element different from another. They have a positive charge (yes, I'm positive that it's a positive charge).

• protons

• electrons

• neutrons

• nucleus

These subatomic particles hang out in the nucleus and don't really affect the properties of the atom that much. They are neutral (don't have any charge).

• neutrons

• protons

• electrons

• atomic numbers

This number tells you how many protons are in each atom of a specific element and how many electrons there are in each unreacted atom from that element.

• atomic number

• atomic mass

• number of electrons

• chemical symbol

Carbon dioxide is formed when two oxygen atoms chemically combine with a carbon atom. Which term best describes carbon dioxide?

• atom
• mixture
• element
• compound

Which statement is true about a mixture?

• A mixture can be described by a chemical formula

• A mixture can be broken down into its basic substances through physical methods

• A mixture is created through a chemical reaction

• A mixture cannot be broken down into simpler substances

What is a compound?

• Two or more than two different elements chemically bonded together.

• Two of the same elements bonded together.

• A mixture of different substances.

• Two substances stuck together with glue.

What does the diagram show?

• A mixture of two elements
• A pure compound
• A mixture of two compounds
• A mixture of a compound & an element

Select the correct definition for an atom.

• The smallest part of an element that can exist.

• A substance made of only one type of atom.

• A substance made of more than one type of atom that are chemically bonded together.

• A substance made of more than one type of atom that are not chemically bonded together.